-[Developing Components in Isolation](#developing-components-in-isolation)
-[Making a Progressive Web App](#making-a-progressive-web-app)
-[Deployment](#deployment)
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@@ -882,6 +883,12 @@ Snapshot testing is a new feature of Jest that automatically generates text snap
This feature is experimental and still [has major usage issues](https://github.com/facebookincubator/create-react-app/issues/372) so we only encourage you to use it if you like experimental technology. We intend to gradually improve it over time and eventually offer it as the default solution for testing React components, but this will take time. [Read more about snapshot testing.](http://facebook.github.io/jest/blog/2016/07/27/jest-14.html)
### Editor Integration
If you use [Visual Studio Code](https://code.visualstudio.com), there is a [Jest extension](https://github.com/orta/vscode-jest) which works with Create React App out of the box. This provides a lot of IDE-like features while using a text editor: showing the status of a test run with potential fail messages inline, starting and stopping the watcher automatically, and offering one-click snapshot updates.

## Developing Components in Isolation
Usually, in an app, you have a lot of UI components, and each of them has many different states.